sound/soc/img/img-spdif-out.c

   1 /*
   2  * IMG SPDIF output controller driver
   3  *
   4  * Copyright (C) 2015 Imagination Technologies Ltd.
   5  *
   6  * Author: Damien Horsley <Damien.Horsley@imgtec.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms and conditions of the GNU General Public License,
  10  * version 2, as published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/clk.h>
  14 #include <linux/init.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/of.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/pm_runtime.h>
  20 #include <linux/reset.h>
  21
  22 #include <sound/core.h>
  23 #include <sound/dmaengine_pcm.h>
  24 #include <sound/initval.h>
  25 #include <sound/pcm.h>
  26 #include <sound/pcm_params.h>
  27 #include <sound/soc.h>
  28
  29 #define IMG_SPDIF_OUT_TX_FIFO           0x0
  30
  31 #define IMG_SPDIF_OUT_CTL               0x4
  32 #define IMG_SPDIF_OUT_CTL_FS_MASK       BIT(4)
  33 #define IMG_SPDIF_OUT_CTL_CLK_MASK      BIT(2)
  34 #define IMG_SPDIF_OUT_CTL_SRT_MASK      BIT(0)
  35
  36 #define IMG_SPDIF_OUT_CSL               0x14
  37
  38 #define IMG_SPDIF_OUT_CSH_UV            0x18
  39 #define IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT  0
  40 #define IMG_SPDIF_OUT_CSH_UV_CSH_MASK   0xff
  41
  42 struct img_spdif_out {
  43         spinlock_t lock;
  44         void __iomem *base;
  45         struct clk *clk_sys;
  46         struct clk *clk_ref;
  47         struct snd_dmaengine_dai_dma_data dma_data;
  48         struct device *dev;
  49         struct reset_control *rst;
  50 };
  51
  52 static int img_spdif_out_suspend(struct device *dev)
  53 {
  54         struct img_spdif_out *spdif = dev_get_drvdata(dev);
  55
  56         clk_disable_unprepare(spdif->clk_ref);
  57
  58         return 0;
  59 }
  60
  61 static int img_spdif_out_resume(struct device *dev)
  62 {
  63         struct img_spdif_out *spdif = dev_get_drvdata(dev);
  64         int ret;
  65
  66         ret = clk_prepare_enable(spdif->clk_ref);
  67         if (ret) {
  68                 dev_err(dev, "clk_enable failed: %d\n", ret);
  69                 return ret;
  70         }
  71
  72         return 0;
  73 }
  74
  75 static inline void img_spdif_out_writel(struct img_spdif_out *spdif, u32 val,
  76                                 u32 reg)
  77 {
  78         writel(val, spdif->base + reg);
  79 }
  80
  81 static inline u32 img_spdif_out_readl(struct img_spdif_out *spdif, u32 reg)
  82 {
  83         return readl(spdif->base + reg);
  84 }
  85
  86 static void img_spdif_out_reset(struct img_spdif_out *spdif)
  87 {
  88         u32 ctl, status_low, status_high;
  89
  90         ctl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL) &
  91                         ~IMG_SPDIF_OUT_CTL_SRT_MASK;
  92         status_low = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
  93         status_high = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
  94
  95         reset_control_assert(spdif->rst);
  96         reset_control_deassert(spdif->rst);
  97
  98         img_spdif_out_writel(spdif, ctl, IMG_SPDIF_OUT_CTL);
  99         img_spdif_out_writel(spdif, status_low, IMG_SPDIF_OUT_CSL);
 100         img_spdif_out_writel(spdif, status_high, IMG_SPDIF_OUT_CSH_UV);
 101 }
 102
 103 static int img_spdif_out_info(struct snd_kcontrol *kcontrol,
 104                                         struct snd_ctl_elem_info *uinfo)
 105 {
 106         uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
 107         uinfo->count = 1;
 108
 109         return 0;
 110 }
 111
 112 static int img_spdif_out_get_status_mask(struct snd_kcontrol *kcontrol,
 113                                        struct snd_ctl_elem_value *ucontrol)
 114 {
 115         ucontrol->value.iec958.status[0] = 0xff;
 116         ucontrol->value.iec958.status[1] = 0xff;
 117         ucontrol->value.iec958.status[2] = 0xff;
 118         ucontrol->value.iec958.status[3] = 0xff;
 119         ucontrol->value.iec958.status[4] = 0xff;
 120
 121         return 0;
 122 }
 123
 124 static int img_spdif_out_get_status(struct snd_kcontrol *kcontrol,
 125                                   struct snd_ctl_elem_value *ucontrol)
 126 {
 127         struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
 128         struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(cpu_dai);
 129         u32 reg;
 130         unsigned long flags;
 131
 132         spin_lock_irqsave(&spdif->lock, flags);
 133
 134         reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
 135         ucontrol->value.iec958.status[0] = reg & 0xff;
 136         ucontrol->value.iec958.status[1] = (reg >> 8) & 0xff;
 137         ucontrol->value.iec958.status[2] = (reg >> 16) & 0xff;
 138         ucontrol->value.iec958.status[3] = (reg >> 24) & 0xff;
 139
 140         reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
 141         ucontrol->value.iec958.status[4] =
 142                 (reg & IMG_SPDIF_OUT_CSH_UV_CSH_MASK) >>
 143                 IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT;
 144
 145         spin_unlock_irqrestore(&spdif->lock, flags);
 146
 147         return 0;
 148 }
 149
 150 static int img_spdif_out_set_status(struct snd_kcontrol *kcontrol,
 151                                   struct snd_ctl_elem_value *ucontrol)
 152 {
 153         struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
 154         struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(cpu_dai);
 155         u32 reg;
 156         unsigned long flags;
 157
 158         reg = ((u32)ucontrol->value.iec958.status[3] << 24);
 159         reg |= ((u32)ucontrol->value.iec958.status[2] << 16);
 160         reg |= ((u32)ucontrol->value.iec958.status[1] << 8);
 161         reg |= (u32)ucontrol->value.iec958.status[0];
 162
 163         spin_lock_irqsave(&spdif->lock, flags);
 164
 165         img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CSL);
 166
 167         reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
 168         reg &= ~IMG_SPDIF_OUT_CSH_UV_CSH_MASK;
 169         reg |= (u32)ucontrol->value.iec958.status[4] <<
 170                         IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT;
 171         img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CSH_UV);
 172
 173         spin_unlock_irqrestore(&spdif->lock, flags);
 174
 175         return 0;
 176 }
 177
 178 static struct snd_kcontrol_new img_spdif_out_controls[] = {
 179         {
 180                 .access = SNDRV_CTL_ELEM_ACCESS_READ,
 181                 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
 182                 .name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, MASK),
 183                 .info = img_spdif_out_info,
 184                 .get = img_spdif_out_get_status_mask
 185         },
 186         {
 187                 .iface = SNDRV_CTL_ELEM_IFACE_PCM,
 188                 .name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, DEFAULT),
 189                 .info = img_spdif_out_info,
 190                 .get = img_spdif_out_get_status,
 191                 .put = img_spdif_out_set_status
 192         }
 193 };
 194
 195 static int img_spdif_out_trigger(struct snd_pcm_substream *substream, int cmd,
 196                         struct snd_soc_dai *dai)
 197 {
 198         struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
 199         u32 reg;
 200         unsigned long flags;
 201
 202         switch (cmd) {
 203         case SNDRV_PCM_TRIGGER_START:
 204         case SNDRV_PCM_TRIGGER_RESUME:
 205         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 206                 reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
 207                 reg |= IMG_SPDIF_OUT_CTL_SRT_MASK;
 208                 img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CTL);
 209                 break;
 210         case SNDRV_PCM_TRIGGER_STOP:
 211         case SNDRV_PCM_TRIGGER_SUSPEND:
 212         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 213                 spin_lock_irqsave(&spdif->lock, flags);
 214                 img_spdif_out_reset(spdif);
 215                 spin_unlock_irqrestore(&spdif->lock, flags);
 216                 break;
 217         default:
 218                 return -EINVAL;
 219         }
 220
 221         return 0;
 222 }
 223
 224 static int img_spdif_out_hw_params(struct snd_pcm_substream *substream,
 225         struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
 226 {
 227         struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
 228         unsigned int channels;
 229         long pre_div_a, pre_div_b, diff_a, diff_b, rate, clk_rate;
 230         u32 reg;
 231         snd_pcm_format_t format;
 232
 233         rate = params_rate(params);
 234         format = params_format(params);
 235         channels = params_channels(params);
 236
 237         dev_dbg(spdif->dev, "hw_params rate %ld channels %u format %u\n",
 238                         rate, channels, format);
 239
 240         if (format != SNDRV_PCM_FORMAT_S32_LE)
 241                 return -EINVAL;
 242
 243         if (channels != 2)
 244                 return -EINVAL;
 245
 246         pre_div_a = clk_round_rate(spdif->clk_ref, rate * 256);
 247         if (pre_div_a < 0)
 248                 return pre_div_a;
 249         pre_div_b = clk_round_rate(spdif->clk_ref, rate * 384);
 250         if (pre_div_b < 0)
 251                 return pre_div_b;
 252
 253         diff_a = abs((pre_div_a / 256) - rate);
 254         diff_b = abs((pre_div_b / 384) - rate);
 255
 256         /* If diffs are equal, use lower clock rate */
 257         if (diff_a > diff_b)
 258                 clk_set_rate(spdif->clk_ref, pre_div_b);
 259         else
 260                 clk_set_rate(spdif->clk_ref, pre_div_a);
 261
 262         /*
 263          * Another driver (eg machine driver) may have rejected the above
 264          * change. Get the current rate and set the register bit according to
 265          * the new min diff
 266          */
 267         clk_rate = clk_get_rate(spdif->clk_ref);
 268
 269         diff_a = abs((clk_rate / 256) - rate);
 270         diff_b = abs((clk_rate / 384) - rate);
 271
 272         reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
 273         if (diff_a <= diff_b)
 274                 reg &= ~IMG_SPDIF_OUT_CTL_CLK_MASK;
 275         else
 276                 reg |= IMG_SPDIF_OUT_CTL_CLK_MASK;
 277         img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CTL);
 278
 279         return 0;
 280 }
 281
 282 static const struct snd_soc_dai_ops img_spdif_out_dai_ops = {
 283         .trigger = img_spdif_out_trigger,
 284         .hw_params = img_spdif_out_hw_params
 285 };
 286
 287 static int img_spdif_out_dai_probe(struct snd_soc_dai *dai)
 288 {
 289         struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
 290
 291         snd_soc_dai_init_dma_data(dai, &spdif->dma_data, NULL);
 292
 293         snd_soc_add_dai_controls(dai, img_spdif_out_controls,
 294                         ARRAY_SIZE(img_spdif_out_controls));
 295
 296         return 0;
 297 }
 298
 299 static struct snd_soc_dai_driver img_spdif_out_dai = {
 300         .probe = img_spdif_out_dai_probe,
 301         .playback = {
 302                 .channels_min = 2,
 303                 .channels_max = 2,
 304                 .rates = SNDRV_PCM_RATE_8000_192000,
 305                 .formats = SNDRV_PCM_FMTBIT_S32_LE
 306         },
 307         .ops = &img_spdif_out_dai_ops
 308 };
 309
 310 static const struct snd_soc_component_driver img_spdif_out_component = {
 311         .name = "img-spdif-out"
 312 };
 313
 314 static int img_spdif_out_probe(struct platform_device *pdev)
 315 {
 316         struct img_spdif_out *spdif;
 317         struct resource *res;
 318         void __iomem *base;
 319         int ret;
 320         struct device *dev = &pdev->dev;
 321
 322         spdif = devm_kzalloc(&pdev->dev, sizeof(*spdif), GFP_KERNEL);
 323         if (!spdif)
 324                 return -ENOMEM;
 325
 326         platform_set_drvdata(pdev, spdif);
 327
 328         spdif->dev = &pdev->dev;
 329
 330         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 331         base = devm_ioremap_resource(&pdev->dev, res);
 332         if (IS_ERR(base))
 333                 return PTR_ERR(base);
 334
 335         spdif->base = base;
 336
 337         spdif->rst = devm_reset_control_get_exclusive(&pdev->dev, "rst");
 338         if (IS_ERR(spdif->rst)) {
 339                 if (PTR_ERR(spdif->rst) != -EPROBE_DEFER)
 340                         dev_err(&pdev->dev, "No top level reset found\n");
 341                 return PTR_ERR(spdif->rst);
 342         }
 343
 344         spdif->clk_sys = devm_clk_get(&pdev->dev, "sys");
 345         if (IS_ERR(spdif->clk_sys)) {
 346                 if (PTR_ERR(spdif->clk_sys) != -EPROBE_DEFER)
 347                         dev_err(dev, "Failed to acquire clock 'sys'\n");
 348                 return PTR_ERR(spdif->clk_sys);
 349         }
 350
 351         spdif->clk_ref = devm_clk_get(&pdev->dev, "ref");
 352         if (IS_ERR(spdif->clk_ref)) {
 353                 if (PTR_ERR(spdif->clk_ref) != -EPROBE_DEFER)
 354                         dev_err(dev, "Failed to acquire clock 'ref'\n");
 355                 return PTR_ERR(spdif->clk_ref);
 356         }
 357
 358         ret = clk_prepare_enable(spdif->clk_sys);
 359         if (ret)
 360                 return ret;
 361
 362         img_spdif_out_writel(spdif, IMG_SPDIF_OUT_CTL_FS_MASK,
 363                                 IMG_SPDIF_OUT_CTL);
 364
 365         img_spdif_out_reset(spdif);
 366
 367         pm_runtime_enable(&pdev->dev);
 368         if (!pm_runtime_enabled(&pdev->dev)) {
 369                 ret = img_spdif_out_resume(&pdev->dev);
 370                 if (ret)
 371                         goto err_pm_disable;
 372         }
 373
 374         spin_lock_init(&spdif->lock);
 375
 376         spdif->dma_data.addr = res->start + IMG_SPDIF_OUT_TX_FIFO;
 377         spdif->dma_data.addr_width = 4;
 378         spdif->dma_data.maxburst = 4;
 379
 380         ret = devm_snd_soc_register_component(&pdev->dev,
 381                         &img_spdif_out_component,
 382                         &img_spdif_out_dai, 1);
 383         if (ret)
 384                 goto err_suspend;
 385
 386         ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
 387         if (ret)
 388                 goto err_suspend;
 389
 390         dev_dbg(&pdev->dev, "Probe successful\n");
 391
 392         return 0;
 393
 394 err_suspend:
 395         if (!pm_runtime_status_suspended(&pdev->dev))
 396                 img_spdif_out_suspend(&pdev->dev);
 397 err_pm_disable:
 398         pm_runtime_disable(&pdev->dev);
 399         clk_disable_unprepare(spdif->clk_sys);
 400
 401         return ret;
 402 }
 403
 404 static int img_spdif_out_dev_remove(struct platform_device *pdev)
 405 {
 406         struct img_spdif_out *spdif = platform_get_drvdata(pdev);
 407
 408         pm_runtime_disable(&pdev->dev);
 409         if (!pm_runtime_status_suspended(&pdev->dev))
 410                 img_spdif_out_suspend(&pdev->dev);
 411
 412         clk_disable_unprepare(spdif->clk_sys);
 413
 414         return 0;
 415 }
 416
 417 static const struct of_device_id img_spdif_out_of_match[] = {
 418         { .compatible = "img,spdif-out" },
 419         {}
 420 };
 421 MODULE_DEVICE_TABLE(of, img_spdif_out_of_match);
 422
 423 static const struct dev_pm_ops img_spdif_out_pm_ops = {
 424         SET_RUNTIME_PM_OPS(img_spdif_out_suspend,
 425                            img_spdif_out_resume, NULL)
 426 };
 427
 428 static struct platform_driver img_spdif_out_driver = {
 429         .driver = {
 430                 .name = "img-spdif-out",
 431                 .of_match_table = img_spdif_out_of_match,
 432                 .pm = &img_spdif_out_pm_ops
 433         },
 434         .probe = img_spdif_out_probe,
 435         .remove = img_spdif_out_dev_remove
 436 };
 437 module_platform_driver(img_spdif_out_driver);
 438
 439 MODULE_AUTHOR("Damien Horsley <Damien.Horsley@imgtec.com>");
 440 MODULE_DESCRIPTION("IMG SPDIF Output driver");
 441 MODULE_LICENSE("GPL v2");